I don't think it's the version of SDL. I'm running version 2.0.8 (which is installed as a required dependency when Hatari is installed). Hatari is version 2.1.0.
The reason I don't think this is the problem, as the red bars don't show up on either a 21.5" iMac (non-retina), nor do they show up on a 13" MacBook Air (also non-retina). In both of these cases, the bars are there, but they're black, so they're effectively invisible.
I'm wondering if there was a way to change the colours of these bars in Hatari configuration or something like that? Because it's unusable with these bright red bars burning my eyes
. Or is this a problem with all retina displays?
Here's a screenshot of it running with black bars on the other computer.
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